This invention relates to a valve intended to be mounted directly on the rim of a vehicle wheel fitted with a “tubeless” tire.
Such a valve is secured to the rim through which it passes and it is known to carry it out using a threaded metal socket passing through the rim, and immobilized by a nut, by the intermediary of a seal.
This has the disadvantage of having a high cost due to the multi-component effect, i.e. a nut, a seal and a valve. This also necessarily generates multiple manipulations during mounting or dismounting.
Valves of the “Snap-In” type are also known, secured to the rim through which they pass by the intermediary of a groove produced at the base of a bulb extended by a rubbery coating of an internal nozzle of the valve, said groove cooperating elastically with a hole in the rim on the periphery of which it becomes housed by force, thanks to the elastic deformation of the groove.
As such the valve can be mounted in a single operation, and without having recourse to intermediary elements such as the nut and the seal.
Nevertheless, tests have made it possible to observe a certain degree of instability of the valve, and even more so when the internal portion of the valve is associated to a pressure sensor box, which increases the mass of the device, and more particularly at high speed.
In this case, the centrifugal force destabilizes the unit due to the tendency to raise the box in the direction of the periphery of the wheel, and consequently, to exert an additional constraint on the rubber of the valve, on the hole in the rim. It has been observed that this results in shearing effects and the initiation of breakage of the rubber comprising the valve, having for consequence to cause leaks that damage the seal of the wheel.
The tests have demonstrated that these detrimental effects due to the centrifugal force take place in the upper portion of the bulb and of the groove of the valve, on the hole in the rim.
It may have been thought to remedy this problem by increasing the thickness of the rubber on the bulb and on the groove, or its hardness over the entire periphery of the groove cooperating with the periphery of the hole in the rim. But this would imply an additional introduction effort during the mounting of the valve in the hole in the rim.